Transition-metal-free synthetic methods have been developed for the preparation of unsymmetrical diaryl and aryl alkyl chalcogenides: sulfones, sulfides, and selenides from the sp-C-H bond of oxindole, tetralone, arylacetamide, and aryl chalcogenide precursors. Sulfones were obtained from sodium sulfinates using potassium iodide, tert-butyl hydroperoxide in DMSO, and acetic acid. Sulfides and selenides were prepared from diaryl disulfides or diselenides employing potassium tert-butoxide in DMSO. α-Tetralone underwent concomitant chalcogenation and aromatization resulting in 2-chalcogenyl-1-naphthols in one pot.

Am ild and efficientp alladium-catalyzed synthetic method for the C À Hf unctionalization of N-(quinolin-8-yl)ferrocenecarboxamide has been developed. Va rious aryl iodides containingI ,N O 2 ,C N, COMe,C O 2 Et, and NH functionalities and also alkyl iodidesu nderwent the Pd-catalyzed intermolecular carbon-carbon bond forming reactionw ith ferrocenecarboxamide successfully which led to ad iverse array of bis(aryl/alkyl)ferrocenecarboxamidesi n3 4-92% yields.C ross-coupling of the ferrocenylC À H bond with aryl iodidesc an also be achieved utilizing an economical Ni catalyst. Additionally,s elective monoalkylation of ferrocenecarboxamide was studied using sodium bicarbonatea sb ase and dibenzylphosphoric acid as additive under Pd-catalyzed reaction conditions.S ubsequently,r emoval of the directing group,8 -aminoquinoline,f rom bis(aryl)ferrocenecarboxamides led to bis(aryl)ferrocenesb earing versatilem ethyl ester andc arboxaldehyde functional groups.Scheme 2. Substrate scope with regard to aryl/heteroaryl iodides.U nlesso therwises tated, isolated yields using 10 mol% of Pd(OAc) 2 in toluene are given.

A KO(t)Bu-mediated intermolecular oxidative C-C coupling of nitroarenes with indoles is presented in DMSO at room temperature in an open flask. By using this mild and economical methodology, syntheses of β-(2/4-nitroaryl)-indoles with sensitive functionalities such as bromo, iodo, cyano, and nitro were achieved chemo- and regioselectively. Synthesized β-(2/4-nitroaryl) indoles were transformed into densely functionalized biindoles, indoloindoles, and (4-aminoaryl)-indoles which demonstrate post-transformation utility of the developed methodology.

A method which avoids metal and halogen for the synthesis of 3-arylthioindoles from indoles and diaryl disulfides using ammonium persulfate in methanol has been presented. Moreover, double C-H sulfenylation of indoles at 2 and 3-positions has also been achieved using iodine and ammonium persulfate.

The coupling of the C(sp)-H bond of ferrocene with toluene avoiding in situ functionalization of both coupling partners has been achieved using palladium and iron dual catalysis. This cross oxidative coupling features regioselectivity to primary and secondary C(sp)-H bonds and chemoselectivity toward the -C(sp)-H over C-I bond of toluene with gram-scale production. It seems Fe(II) catalyst not only stabilizes the generated benzyl radical but also tames its oxidizing behavior, and consequently transfers it to the palladacycle for C-C coupling.